Flat nodular lymphoid hyperplasia resembling "apple tree branches" in the colon.

Abstract

A 19-year-old woman with a history of adjustment disorder presented with abdominal pain, bloating, and chronic diarrhea. Colonoscopy revealed multiple flat whitish areas, less than 3 mm in diameter, diffusely distributed throughout the entire colon and rectum. These findings were prominent under narrow-band imaging (NBI) ([Fig. 1 a]) and more difficult to distinguish with white-light imaging ([Fig. 1 b]). The flat areas and the surrounding superficial vessels were described in the report as resembling “apple tree branches” ([Video 1]). Inspection of the terminal ileum was unremarkable, and esophagogastroduodenoscopy was unrevealing. Histologic examination of the colonic biopsy specimens showed nodules of benign lymphoid tissue with enlarged germinal centers and an intact mantle zone, consistent with a diagnosis of nodular lymphoid hyperplasia (NLH) ([Fig. 2]). Laboratory investigations and fecal calprotectin were within normal limits. Stool pathogen testing was negative. The patient was diagnosed with irritable bowel syndrome (IBS) and diffuse flat NLH.